A power miter saw is a cutting tool used to make crosscuts in a work piece, such as a piece of wood. Miter saws typically include a base equipped with a turntable and fence. The turntable is rotatable in relation to the base and has an upper surface that supports a work piece during cutting operations. The fence extends over the turntable to provide an abutment surface for locating an edge of the work piece at a predetermined position on the base.
The saw assembly of the miter saw includes a bevel arm, a cutting arm, and a cutting assembly. The bevel arm is pivotably attached to the turntable for pivotal movement about a bevel axis. The cutting arm is in turn pivotably attached to the bevel arm for pivotal movement toward and away from the turntable. The cutting arm supports the cutting assembly, comprising a circular saw blade and a motor, above the turntable. During cutting operations, the cutting arm is pivoted downwardly to bring the saw blade into contact with a work piece positioned on the turntable.
A typical miter saw includes a fence positioned adjacent the saw blade to serve as a stop for the workpiece. The miter saw generally includes a fence on each side of the saw blade to retain the workpiece in a fixed position as the saw blade cuts through the workpiece. Industry standards require that the clearance between the sides of the saw blade and the fence is less than 8 mm with the saw blade at zero degrees miter and bevel to ensure proper horizontal support for the workpiece. During a bevel or miter cut, however, the saw blade may be rotated to a position at which the fence can interfere with the cut. As a result, a portion of the fence must be moved so that the saw blade can be angled relative to the blade.
In typical miter saws, a one piece fence can be used. The one piece fence is fixed at a position such that it is less than 8 mm from the saw blade at all times. In order to perform a miter or bevel cut, the one piece fence must be removed from the saw so that the fence does not interfere with the saw blade during a cut. This generally requires additional effort of removing bolts from the fence to detach it, and then requiring the fence to be re-aligned upon reattachment. Furthermore, when the fence is removed, it no longer functions to provide horizontal support to the workpiece during a cut.
In other prior art miter saws, the fence includes two pieces. A lower piece is fixedly mounted to the saw frame and is configured such that it does not interfere with miter and bevel cuts. This lower piece, however, must be positioned more than 8 mm from the saw blade in order to avoid interference during miter and bevel cuts. An upper piece of the fence is positioned above the lower piece at a distance of 8 mm or less from the saw blade to provide the required horizontal support. The upper piece of the fence is configured to be moved or detached to avoid interference with the blade during a miter or bevel cut. Forming a fence of two separate pieces increases the cost of the fence assembly. Furthermore, the lower piece is fixed to the saw, while the upper piece requires additional mounting fasteners to attach the upper piece to the lower piece or the saw assembly. Again, moving the upper piece of the fence to perform a miter or bevel cut requires additional effort by the user and may require realignment of the fence.
What is needed, therefore, is a miter saw fence that can be positioned within 8 mm of the saw blade for straight cuts, but is movable relative to the saw blade so that the fence does not interfere with the saw blade during miter and bevel cuts. Additionally, a miter saw fence that does not require realignment before and/or after performing a miter or bevel cut would be advantageous.